Evaluate the structure of the dataframe using the str() function to make sure that it got read in correctly. It should have 2524 observations of 86 variables.

Create a new dataframe containing only the XFB, OBB, and SIS varibles

Add a new column to the new dataframe that is the product of the XFB, OBB, and SIS variables.

Problem 2

Using dplyr, calculate the mean of the GOL, XCB, ZYB and SIS measurements for each population group by sex. (i.e., calculate the mean value separately for NORSE males and NORSE females, and likewise for all groups). The resulting data frame should only have 6 columns. (one each for sex and population, and one for each of the 4 measurements).

Recreate the below figure exactly (including the theme) using the full cranial dataset. Note: you can control the size of the figures in your knitted document by including options in the code chunk. The default size is 6 for width and height. The figure below is 16 wide and 9 high, like the following.